Safe energy-storage mechanical metamaterials via architecture design

Mechanical and functional properties of metamaterials could be simultaneously manipulated via their architectures. This study proposes multifunctional metamaterials possessing both load-bearing capacity and energy storage capability, comprising multi-phase lattice metamaterial and cylindrical battery cells. Defect phase are incorporated into the metamaterials, which are then printed with stainless steel powder. The printed metamaterials are assembled with battery cells and compressed. Experimental results revealed that the voids in the lattice metamaterials, could guide deformation mode away from the internal battery cell that postponed the emergence of battery short-circuit. Effects of void phase pattern and content are discussed by simulation. We found that the multifunctional system could absorb greater energy after defect phase incorporation, as designed with proper void phase pattern and content. Also, these findings are further validated for the system with six battery cells. This study demonstrated how to design an energy-storage metamaterials with enhanced mechanical properties and battery safety simultaneously. Also, defect engineering was helpful for battery protection and energy absorption of the multifunctional system.